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基于专利分析的质量计量技术发展态势研究

计量与测试技术 2024年第5期51卷 72-74页

作者：杜晓曼北京市西城区计量检测所

质量计量作为计量工作的重要组成部分,是工业生产中的重要环节,对保证产品质量,提高生产效率具有重要意义。本文旨在从发展趋势、技术分布、创新主体等维度,对我国质量计量技术相关的专利文献进行分析研究,使计量工作者能更好的了解掌... 详细信息

质量计量作为计量工作的重要组成部分,是工业生产中的重要环节,对保证产品质量,提高生产效率具有重要意义。本文旨在从发展趋势、技术分布、创新主体等维度,对我国质量计量技术相关的专利文献进行分析研究,使计量工作者能更好的了解掌握其专利分布态势,并促进该领域的产、学、研、用各主体之间能更好的了解整体情况。

关键词：计量质量专利

电子天平检定过程中的注意事项及不确定度评定探讨

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品牌与标准化 2024年第3期 232-234页

作者：杜晓曼北京市西城区计量检测所北京100055

本文结合国家规程要求和实际工作经验,梳理了电子天平检定过程中的注意事项,并以一台210 g/0.01 mg的电子天平测量结果的不确定度评定为例进行探讨。这样的探讨可以为计量检定人员提供指导,让他们注意在检定过程中可能存在的问题,并严... 详细信息

本文结合国家规程要求和实际工作经验,梳理了电子天平检定过程中的注意事项,并以一台210 g/0.01 mg的电子天平测量结果的不确定度评定为例进行探讨。这样的探讨可以为计量检定人员提供指导,让他们注意在检定过程中可能存在的问题,并严格按照计量检定规程进行工作。

关键词：电子天平检定不确定度

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对计量行业中知识产权工作的思考

仪器仪表标准化与计量 2024年第3期 10-11,19页

作者：杜晓曼北京市西城区计量检测所北京市100055

计量是实现单位统一、保证量值准确可靠的活动,是关于测量及其应用的科学,也是科技创新、产业发展、国防建设、民生保障的重要基础。本文旨在从以知识产权为抓手,推动计量领域科技自立自强;以知识产权为纽带,加强计量领域成果保护和成... 详细信息

计量是实现单位统一、保证量值准确可靠的活动,是关于测量及其应用的科学,也是科技创新、产业发展、国防建设、民生保障的重要基础。本文旨在从以知识产权为抓手,推动计量领域科技自立自强;以知识产权为纽带,加强计量领域成果保护和成果转化;以知识产权为牵引,促进计量领域产业链创新链对接等角度,对计量行业中的知识产权工作进行探讨。

关键词：计量创新知识产权

Statistical analysis on the validity of the cold plasma approximation for chorus waves based on Van Allen Probe observations and their effects on radiation belt electrons

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Earth and Planetary Physics 2025年第1期9卷 159-170页

作者： AoJun Ren Jiang Yu Jing Wang ZuZheng Chen xiaoman Liu Planetary Environmental and Astrobiological Research Laboratory(PEARL) School of Atmospheric SciencesSun Yat-sen UniversityZhuhai Guangdong 519000China

Theoretical analysis has demonstrated that the dispersion relation of chorus waves plays an essential role in the resonant interaction and energy transformation between the waves and magnetospheric *** quantitative analyses often simplified the chorus dispersion relation by using the cold plasma ***,the applicability of the cold plasma assumption is doubtful,especially during geomagnetic *** here present a systematic statistical analysis on the validity of the cold plasma dispersion relation of chorus waves based on observations from the Van Allen Probes over the period from 2012 to *** statistical results show that the observed magnetic field intensities deviate substantially from those calculated from the cold plasma dispersion relation and that they become more pronounced with an increase in geomagnetic activity or a decrease in background plasma *** region with large deviations is mainly concentrated in the nightside and expands in both the radial and azimuthal directions as the geomagnetic activity increases or the background plasma density *** addition,the bounce-averaged electron scattering rates are computed by using the observed and cold plasma dispersion relation of chorus *** with usage of the cold plasma dispersion relation,usage of the observed dispersion relation considerably lowers the minimum resonant energy of electrons and lowers the scattering rates of electrons above tens of kiloelectronvolts but enhances those ***,these differences are more pronounced with the enhancement of geomagnetic activity or the decrease in background plasma density.

关键词： chorus waves cold plasma approximation dispersion relations scattering rates

A Decoupling-Type Strategy for the Allen-Cahn Equation on Curved Surfaces

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Journal of Mathematical Research with Applications 2025年第1期 73-83页

作者： xiaoman XIE Qing PAN School of Computer and Communication Engineering Changsha University of Science & Technology

In this paper, we construct an efficient decoupling-type strategy for solving the Allen-Cahn equation on curved surfaces. It is based on an FEM-EIEQ(Finite Element Method and explicit-Invariant Energy Quadratization) fully discrete scheme with unconditional energy stability. Spatially the FEM is adopted, using a triangular mesh discretization strategy that can be adapted to complex regions. Temporally, the EIEQ approach is considered, which not only linearizes the nonlinear potential but also gives a new variable that we combine with the nonlocal splitting method to achieve the fully decoupled computation. The strategy can successfully transform the Allen-Cahn system into some completely independent algebraic equations and linear elliptic equations with constant coefficients, we only need to solve these simple equations at each time step. Moreover, we conducted some numerical experiments to demonstrate the effectiveness of the strategy.

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煅烧煤系高岭土和硅粉用于混凝土的对比试验

金属矿山 2010年第9期39卷 170-172,187页

作者：杜小满刘钦甫邢楠张金山程宏飞中国矿业大学北京内蒙古科技大学北京建筑工程学院

用煅烧煤系高岭土细粉按一定比例等量取代水泥配制C50高性能混凝土,系统研究了硬化混凝土的力学性能和耐久性能。用工程常用的活性掺合料硅粉作平行试验进行对比,探讨煅烧煤系高岭土细粉代替硅粉用作混凝土活性矿物掺合料的可行性。试... 详细信息

用煅烧煤系高岭土细粉按一定比例等量取代水泥配制C50高性能混凝土,系统研究了硬化混凝土的力学性能和耐久性能。用工程常用的活性掺合料硅粉作平行试验进行对比,探讨煅烧煤系高岭土细粉代替硅粉用作混凝土活性矿物掺合料的可行性。试验结果表明,经700℃热处理得到的煅烧煤系高岭土具有相当高的水化活性,当掺量同为10%时,掺煅烧煤系高岭土混凝土具有良好的力学性能和耐久性能,而且其对混凝土抗折性能的增强效果优于硅粉。

关键词：煅烧高岭土煤系高岭土硅粉混凝土

Large-brained birds lay smaller but heavier clutches

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Avian Research 2023年第3期14卷 460-466页

作者： Shaobin Li xiaoman Liu Guopan Li Xiaolong du College of Life Science Yangtze UniversityJingzhou40025China

The brain is among the most energetically costly organs in vertebrates,and thus trade-offs have been hypothesized to exert constraints on brain size *** energy trade-off hypothesis(ETH) predicts that reducing the energy consumption of reproduction or other costly tissues should compensate for the cost of a large *** production in birds requires a large proportion of the total energy budget,and a clutch mass in some bird species can outweigh the body mass of the *** date,this hypothesis has mainly been tested in mammals and ectothermic animals such as anurans and *** collated data on adult brain size,body mass and eggproduction traits such as clutch size,egg mass and annual broods from published studies,and conducted a phylogenetic comparative test of the interplay between egg-production investment and brain size evolution across bird *** controlling for phylogenetic relationships and body size,we find a negative correlation between brain size and clutch size across 1395 species,which favored ***,when egg mass was integrated in models,positive associations were detected between brain size and mass of eggs(via egg mass,clutch mass and annual total egg mass).Our results suggest that brain size trades off against egg-production only via certain aspects(e.g.,clutch size).By contrast,a positive relationship between brain size and total egg reproduction(e.g.,clutch mass and annual total egg mass) implied increased total energy budget outweighing energy allocation across bird *** study shows that there is no general energy trade-off between brain size and eggreproduction investment,and suggests that brain size evolution follows mixed strategies across bird species.

关键词： Brain size Breeding attempts Clutch size Comparative analysis Egg mass Reproduction investment Trade-off

Evolutionary analysis and lineage designation of SARS-CoV-2 genomes

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Science Bulletin 2021年第22期66卷 2297-2311,M0004页

作者： Xiaolu Tang Ruochen Ying Xinmin Yao Guanghao Li Changcheng Wu Yiyuli Tang Zhida Li Bishan Kuang Feng Wu Changsheng Chi xiaoman du Yi Qin Shenghan Gao Songnian Hu Juncai Ma Tiangang Liu Xinghuo Pang Jianwei Wang Guoping Zhao Wenjie Tan Yaping Zhang Xuemei Lu Jian Lu State Key Laboratory of Protein and Plant Gene Research Center for BioinformaticsSchool of Life SciencesPeking UniversityBeijing 100871China State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyCenter for Excellence in Animal Evolution and GeneticsChinese Academy of SciencesKunming 650223China Beijing Institute of Genomics Chinese Academy of SciencesBeijing 100101China Yuxi Rongjian Information Technology Co. Ltd.Yuxi 653100China State Key Laboratory of Microbial Resources(SKLMR) The Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China The Microresource and Big Data Center The Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China Key Laboratory of Combinatorial Biosynthesis and Drug Discovery Ministry of Education and Wuhan University School of Pharmaceutical SciencesWuhan 430071China Beijing Center for Disease Prevention and Control(CDC)&Research Center for Preventive Medicine of Beijing Beijing 100013China NHC Key Laboratory of Systems Biology of Pathogens and Christophe Mérieux Laboratory Institute of Pathogen BiologyChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China Key Laboratory of Respiratory Disease Pathogenomics Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China Key Laboratory of Synthetic Biology Institute of Plant Physiology and EcologyShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghai 200032China NHC Key Laboratory of Biosafety National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China

The pandemic due to the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),the etiological agent of coronavirus disease 2019(COVID-19),has caused immense global *** the rapid accumulation of SARS-CoV-2 genome sequences,however,thousands of genomic variants of SARSCoV-2 are now publicly *** improve the tracing of the viral genomes’evolution during the development of the pandemic,we analyzed single nucleotide variants(SNVs)in 121,618 high-quality SARS-CoV-2 *** divided these viral genomes into two major lineages(L and S)based on variants at sites 8782 and 28144,and further divided the L lineage into two major sublineages(L1 and L2)using SNVs at sites 3037,14408,and ***,we categorized them into 130 sublineages(37 in S,35 in L1,and 58 in L2)based on marker SNVs at 201 additional genomic *** lineage/sublineage designation system has a hierarchical structure and reflects the relatedness among the subclades of the major *** also provide a companion website(***)that allows users to visualize sublineage information and upload their own SARS-CoV-2 genomes for sublineage ***,we discussed the possible roles of compensatory mutations and natural selection during SARS-CoV-2’s *** efforts will improve our understanding of the temporal and spatial dynamics of SARS-CoV-2’s genome evolution.

关键词： COVID-19 Evolutionary analysis Compensatory advantageous mutation Adaptive evolution Lineage designation

Effect of dietary supplement of inactivated Lactobacillus plantarum Ep-M 17 on growth performance,immune response,disease resistance,and intestinal microbiota in Penaeus vannamei

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Journal of Oceanology and Limnology 2024年第2期42卷 676-694页

作者： Ting WU xiaoman HU Wenlong XU Yang du Jiong CHEN State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products Ningbo UniversityNingbo 315211China Laboratory of Biochemistry and Molecular Biology School of Marine SciencesNingbo UniversityNingbo 315211China Key Laboratory of Applied Marine Biotechnology of Ministry of Education Ningbo UniversityNingbo 315211China

Our previous study found that feeding with Lactobacillus plantarum Ep-M17 could effectively affect the growth performance,immune response,and gut microbiota of Penaeus ***,high temperature and pressure during feed pelletizing is the main problem that can lead to a decrease in the activity of probiotics or cause their *** investigation needs to investigate whether inactivated Ep-M17 can exert similar effects as live ***,we evaluated the effects of inactivated *** Ep-M17 on growth performance,immune response,disease resistance,and gut microbiota in *** show that adding inactivated Ep-M17 to the feed also promoted body weight gain and increased relative immune protection in ***,histological examination revealed that the administration of inactivated Ep-M17 led to improvements in the density and distribution of microvilli in the intestines and enhancements in the abundance of B and R cells in the ***,the inactivated Ep-M17 supplementation resulted in increased activity levels of nutrient immune-related enzymes in both the shrimp hepatopancreas and ***,it stimulated the expression of Lvlec,PEN-3a,Crustin,LGBP,Lysozyme,and proPo genes in both the hepatopancreas and ***,the inactivated Ep-M17 also increased bacterial diversity in the gut of shrimp and promoted the abundance of specific flora,facilitating the host organism’s metabolism and immunity to improve the disease resistance of ***,supplementation of inactivated *** Ep-M17 in shrimp diets can exert similar effects as live *** Ep-M17 effectively improving growth performance,gut microbiota,immune response,and disease resistance in ***.

关键词： Penaeus vannamei Lactobacillus plantarum Ep-M17 inactivated probiotics immune response gut flora